MMCSD

Table of Contents

• Features Supported
• SysConfig Features
• Features not Supported
• Example Usage
• API

Multi-Media Card Secure Digital (MMCSD) peripheral is a driver which provides an interface with storage devices which follows MMC/SD/SDIO protocol. The driver supports single bit, four bit and eight bit data lines to communicate with the connected media.

The MMCSD controller provides accessibility to external MMC/SD/SDIO devices using a programmed IO method or DMA data transfer method. There are two MMCSD modules inside the SOC - MMCSD0 ,MMCSD1 and MMCSD2.

Features Supported

• Integrated DMA Controller supporting SD Advanced DMA - SDMA, ADMA2 and ADMA3
• 64-bit data, address width System Bus Interface
• One controller with 8-bit wide data bus
• Two controllers with 4-bit wide data bus
• MMC0 interface is compliant with the JEDEC eMMC electrical standard v5.1 (JESD84-B51) and it supports the following eMMC applications: HS200, HS400
• MMC1/MMC2 interface is compliant with the SD Host Controller Standard Specification 4.10 and SD Physical Layer Specification v3.01 as well as SDIO Specification v3.00 and it supports the following SD Card applications: Default speed, High speed.

Note

The driver assumes the current core voltage is 0.85 V. The OTAPDLYSEL value changes based on the core voltage. Users need to make the following change in the driver if the core voltage is changed to 0.75 V:

diff --git a/source/drivers/mmcsd/v0/mmcsd_v0.c b/source/drivers/mmcsd/v0/mmcsd_v0.c
index 0b100a4293c..293b204babf 100644
--- a/source/drivers/mmcsd/v0/mmcsd_v0.c
+++ b/source/drivers/mmcsd/v0/mmcsd_v0.c
@@ -2765,8 +2765,8 @@ static void MMCSD_phyGetOtapDelay(uint32_t *outputTapDelaySel, uint32_t *outputT
             break;
         case MMCSD_PHY_MODE_HS400:
             *outputTapDelaySel = 1U;
-            /* Output tap delay value for 0.85V Core Voltage */
-            *outputTapDelayVal = MMCSD_OTAPDLYSEL_MMC_HS400_0_85V;
+            /* Output tap delay value for 0.75V Core Voltage */
+            *outputTapDelayVal = MMCSD_OTAPDLYSEL_MMC_HS400_0_75V;
             *inputTapDelaySel = 1U;
             *inputTapDelayVal = tunedItap;
             break;

SysConfig Features

Note

It is strongly recommend to use SysConfig where it is available instead of using direct SW API calls. This will help simplify the SW application and also catch common mistakes early in the development cycle.

Features not Supported

• MMCSD0 does not support SD card, SDIO and voltages 3.0V and 1.2V.
• MMCSD1 does not support MMC card, UHS-II SD card and SDR50, DDR50 and SDR104.

Example Usage

Include the below file to access the APIs

#include <stdio.h>
#include <drivers/mmcsd.h>

Instance Open Example

    MMCSD_Params mmcsdParams;
 
    MMCSD_Params_init(&mmcsdParams);
    gMmcsdHandle = MMCSD_open(0, &mmcsdParams);
    DebugP_assert(gMmcsdHandle != NULL);

Instance Close Example

    MMCSD_close(gMmcsdHandle);

API

APIs for MMCSD